The Middle Valley of the Tiber River, Central Italy: Plio-Pleistocene Fluvial and Coastal Sedimentation, Extensional Tectonics and Volcanism
- Michael D. Blum3,
- Susan B. Marriott4,
- Suzanne F. Leclair5
Published Online: 17 MAR 2009
DOI: 10.1002/9781444304350.ch20
Copyright © 2005 International Association of Sedimentologists
Book Title
Fluvial Sedimentology VII
Additional Information
How to Cite
Mancini, M. and Cavinato, G. P. (2009) The Middle Valley of the Tiber River, Central Italy: Plio-Pleistocene Fluvial and Coastal Sedimentation, Extensional Tectonics and Volcanism, in Fluvial Sedimentology VII (eds M. D. Blum, S. B. Marriott and S. F. Leclair), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304350.ch20
Editor Information
- 3
Baton Rouge, Louisiana, USA
- 4
School of Geography and Environmental Management, University of the West of England, Bristol BS16 1QY, UK
- 5
Department of Earth and Environmental Sciences, Tulane University, Dimwiddie Hall, New Orleans, LA 70118, USA
Publication History
- Published Online: 17 MAR 2009
- Published Print: 15 FEB 2005
Book Series:
Book Series Editors:
- Ian Jarvis
Series Editor Information
School of Earth Sciences and Geography, Centre for Earth and Environmental Science Research, Kingston University, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK
ISBN Information
Print ISBN: 9781405126519
Online ISBN: 9781444304350
- Summary
- Chapter
Keywords:
- fluvial and coastal sedimentation, extensional tectonics and volcanism;
- middle Valley of Tiber River, Italy (MVT);
- WSW–ENE directed extensional regime;
- general tectonic setting;
- palaeoclimatic setting;
- MVT basin stratigraphy;
- Uppermost Lower Pleistocene–Holocene units;
- Sipicciano Unit - the lowest and youngest terraced fluvial deposit of MVT
Summary
The Middle Valley of the Tiber River, Italy (MVT), corresponds to a NNW–SSE trending extensional basin that has developed since the middle Pliocene along the western flank of the central Apennines. Stratigraphical, sedimentological, palaeontological and Sr isotope analyses have been conducted to detail the stratigraphy of the MVT and to reconstruct the history of Pliocene–Quaternary basin filling. Most of the basin-fill is composed of fluvial and deltaic deposits that are chronologically constrained by biostratigraphical data and Sr isotopes from marine deposits, and through relationships with volcanic and volcaniclastic units with K/Ar and Ar/Ar radiometric ages. This paper focuses on relationships between sedimentary phases, long-term (> 1 Myr) tectonic movements, shorter term (100 kyr) climatic and eustatic changes, and volcanism, within the overall extensional tectonic context of the MVT.
Two main tectonic phases are recognized in the MVT, each recorded by the responses of the mostly gravel-dominated fluvial and deltaic systems. The first phase encompasses the middle Pliocene to earliest Early Pleistocene, and was dominated by rapid subsidence. This phase was characterized by transverse rivers that fed cyclically prograding and retrograding fluvial–deltaic wedges, with interfingering marine deposits, and within an overall aggradational context. Superimposed on this overall aggradational trend is an inferred 4th order cyclicity that is interpreted to reflect eustatic and climatic changes. The second phase began in the late Early Pleistocene and extends to the present, and is linked to uplift of the Apennines. This phase was characterized by complete emergence of the MVT, the occurrence of volcanism, development of the Tiber River system, and the initiation of a long-term trend of uplift-driven net valley incision. Alternating aggradational and degradational phases are superimposed on this longer term trend, and are thought to be linked to Late Quaternary climatic forcing, with 100 kyr glacial–interglacial cycles important in the upper reaches of the fluvial system, and the related effects of glacio-eustasy important farther downstream.